Which of the Following Observations Seems to Undermine the Basic

Which of the following observations seems to undermine the basic idea of set-point theory?

A) Although laboratory mice and rats will overeat if given a variety of foods to eat, animals in the wild will only eat enough to maintain a normal body weight.
B) Many people have a strong tendency to gain excessive weight as they get older.
C) Even when people are given medications that boost brain levels of serotonin, their weight will gradually decrease with age.
D) The prevalence of obesity is just as great in developing countries as in North America.